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<a name="PDP_002d11-Options"></a>
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<a name="PDP_002d11-Options-1"></a>
<h4 class="subsection">3.19.37 PDP-11 Options</h4>
<a name="index-PDP_002d11-Options"></a>

<p>These options are defined for the PDP-11:
</p>
<dl compact="compact">
<dd><a name="index-mfpu-3"></a>
</dd>
<dt><code>-mfpu</code></dt>
<dd><p>Use hardware FPP floating point.  This is the default.  (FIS floating
point on the PDP-11/40 is not supported.)  Implies -m45.
</p>
<a name="index-msoft_002dfloat-10"></a>
</dd>
<dt><code>-msoft-float</code></dt>
<dd><p>Do not use hardware floating point.
</p>
<a name="index-mac0"></a>
</dd>
<dt><code>-mac0</code></dt>
<dd><p>Return floating-point results in ac0 (fr0 in Unix assembler syntax).
</p>
<a name="index-mno_002dac0"></a>
</dd>
<dt><code>-mno-ac0</code></dt>
<dd><p>Return floating-point results in memory.  This is the default.
</p>
<a name="index-m40"></a>
</dd>
<dt><code>-m40</code></dt>
<dd><p>Generate code for a PDP-11/40.  Implies -msoft-float -mno-split.
</p>
<a name="index-m45"></a>
</dd>
<dt><code>-m45</code></dt>
<dd><p>Generate code for a PDP-11/45.  This is the default.
</p>
<a name="index-m10"></a>
</dd>
<dt><code>-m10</code></dt>
<dd><p>Generate code for a PDP-11/10.  Implies -msoft-float -mno-split.
</p>
<a name="index-mint16"></a>
<a name="index-mno_002dint32"></a>
</dd>
<dt><code>-mint16</code></dt>
<dt><code>-mno-int32</code></dt>
<dd><p>Use 16-bit <code>int</code>.  This is the default.
</p>
<a name="index-mint32-1"></a>
<a name="index-mno_002dint16"></a>
</dd>
<dt><code>-mint32</code></dt>
<dt><code>-mno-int16</code></dt>
<dd><p>Use 32-bit <code>int</code>.
</p>
<a name="index-msplit"></a>
</dd>
<dt><code>-msplit</code></dt>
<dd><p>Target has split instruction and data space.  Implies -m45.
</p>
<a name="index-munix_002dasm"></a>
</dd>
<dt><code>-munix-asm</code></dt>
<dd><p>Use Unix assembler syntax.
</p>
<a name="index-mdec_002dasm"></a>
</dd>
<dt><code>-mdec-asm</code></dt>
<dd><p>Use DEC assembler syntax.
</p>
<a name="index-mgnu_002dasm"></a>
</dd>
<dt><code>-mgnu-asm</code></dt>
<dd><p>Use GNU assembler syntax.  This is the default.
</p>
<a name="index-mlra-2"></a>
</dd>
<dt><code>-mlra</code></dt>
<dd><p>Use the new LRA register allocator.  By default, the old &ldquo;reload&rdquo;
allocator is used.
</p></dd>
</dl>




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